Storage devices enable users to store and retrieve data. Examples of storage devices include volatile memory devices and non-volatile memory devices. Portions of a memory device may be defective. For example, one or more storage elements of the memory device may be defective. A defective storage element may be unreliable. For example, a defective storage element may not be reliably programmed to a particular state. To illustrate, a first value written to the storage element may not match a second value read from the storage element. In some cases, the memory device may include a bad bit line. For example, multiple storage elements coupled to a bad bit line may be defective. The memory device may include an array of storage elements. The array may include multiple columns of storage elements. Each column may include multiple bit lines. For example, a column may include storage elements coupled to a first number (e.g., 16) of bit lines. A column containing at least one bad (e.g., defective) bit line may be considered a bad column.
A memory device may include redundant storage elements. A bad column may be replaced with a first column of the redundant storage elements. In this case, read/write circuitry of the memory device redirects read/write accesses from the bad column to the first column. The bad column may be designated as unavailable. In this case, even if fewer than all of the bit lines of the column are defective, the entire bad column is replaced. Storage elements coupled to non-bad bit lines of the column are replaced with redundant storage elements, reducing the number of redundant storage elements available to replace other defective storage elements. Some of the storage capacity of the memory device corresponding to elements coupled to non-bad bit lines of a bad column may be wasted (e.g., unused) when an entire bad column is designated as unavailable due to the presence of one or more few bad bit lines in the bad column.